public class Computer {
    public void powerOn(){
        System.out.println("打开笔记本电脑");
    }

    public void powerOff(){
        System.out.println("关闭笔记本电脑");
    }

    public void useDevice(Usb usb){
        usb.openDevice();
        if (usb instanceof Mouse){
            Mouse mouse = (Mouse)usb;
            mouse.click();
        } else if (usb instanceof KeyBoard) {
            KeyBoard keyBoard = (KeyBoard) usb;
            keyBoard.inPut();

        }
        usb.closeDevice();
    }
}
